优化在不指定解析类型的情况下 Gson 默认将数值用 double 类型接收的问题

README.md

@@ -39,10 +39,10 @@ android {
 
 dependencies {
     // Gson 解析容错：https://github.com/getActivity/GsonFactory
-    implementation 'com.github.getActivity:GsonFactory:9.5'
+    implementation 'com.github.getActivity:GsonFactory:9.6'
     // Json 解析框架：https://github.com/google/gson
     implementation 'com.google.code.gson:gson:2.10.1'
-    // Kotlin 反射库：用于反射 Kotlin data class 类对象
+    // Kotlin 反射库：用于反射 Kotlin data class 类对象，1.5.10 请修改成当前项目 Kotlin 的版本号
     implementation 'org.jetbrains.kotlin:kotlin-reflect:1.5.10'
 }
 ```

app/build.gradle

@@ -8,8 +8,8 @@ android {
         applicationId "com.hjq.gson.factory.demo"
         minSdkVersion 26
         targetSdkVersion 31
-        versionCode 950
-        versionName "9.5"
+        versionCode 960
+        versionName "9.6"
         testInstrumentationRunner 'androidx.test.runner.AndroidJUnitRunner'
     }
 

app/src/androidTest/assets/AbnormalJson.json

@@ -47,6 +47,7 @@
     "d": "哈哈",
     "e": false
   },
+  "map5" : 1.1,
   "stringTest1" : null,
   "stringTest2" : false,
   "stringTest3" : 123,

app/src/androidTest/assets/NormalJson.json

@@ -42,6 +42,11 @@
   },
   "map3" : {},
   "map4" : null,
+  "map5" : {
+    "attitude": 1710126441000,
+    "type": 1,
+    "money": 1.2345
+  },
   "stringTest1" : null,
   "stringTest2" : "",
   "stringTest3" : "字符串"

app/src/androidTest/java/com/hjq/gson/factory/test/JsonBean.java

@@ -65,6 +65,7 @@ public final class JsonBean {
     private Map<String, Integer> map2;
     private Map<String, Integer> map3;
     private Map<String, Integer> map4;
+    private Map<String, Object> map5;
 
     private String stringTest1;
     private String stringTest2;

library/build.gradle

@@ -6,8 +6,8 @@ android {
 
     defaultConfig {
         minSdkVersion 12
-        versionCode 950
-        versionName "9.5"
+        versionCode 960
+        versionName "9.6"
     }
 
     // 使用 JDK 1.8

library/src/main/java/com/hjq/gson/factory/GsonFactory.java

@@ -5,6 +5,7 @@
 import com.google.gson.GsonBuilder;
 import com.google.gson.InstanceCreator;
 import com.google.gson.ReflectionAccessFilter;
+import com.google.gson.ToNumberStrategy;
 import com.google.gson.TypeAdapterFactory;
 import com.google.gson.internal.Excluder;
 import com.google.gson.internal.bind.TypeAdapters;
@@ -21,6 +22,7 @@
 import com.hjq.gson.factory.element.CollectionTypeAdapterFactory;
 import com.hjq.gson.factory.element.MapTypeAdapterFactory;
 import com.hjq.gson.factory.element.ReflectiveTypeAdapterFactory;
+import com.hjq.gson.factory.other.AutoToNumberStrategy;
 import java.lang.reflect.Type;
 import java.math.BigDecimal;
 import java.util.ArrayList;
@@ -44,6 +46,8 @@ public final class GsonFactory {
 
     private static final List<ReflectionAccessFilter> REFLECTION_ACCESS_FILTERS = new ArrayList<>();
 
+    private static ToNumberStrategy sObjectToNumberStrategy = new AutoToNumberStrategy();
+
     private static ParseExceptionCallback sParseExceptionCallback;
 
     private static volatile Gson sGson;
@@ -106,19 +110,29 @@ public static void registerInstanceCreator(Type type, InstanceCreator<?> creator
     /**
      * 添加反射访问过滤器，同等于 {@link GsonBuilder#addReflectionAccessFilter(ReflectionAccessFilter)}
      */
-    public void addReflectionAccessFilter(ReflectionAccessFilter filter) {
+    public static void addReflectionAccessFilter(ReflectionAccessFilter filter) {
         if (filter == null) {
             return;
         }
         REFLECTION_ACCESS_FILTERS.add(0, filter);
     }
 
+    /**
+     * 设置自动转换数值类型的策略
+     */
+    public static void setObjectToNumberStrategy(ToNumberStrategy objectToNumberStrategy) {
+        GsonFactory.sObjectToNumberStrategy = objectToNumberStrategy;
+    }
+
     /**
      * 创建 Gson 构建对象
      */
     public static GsonBuilder newGsonBuilder() {
         GsonBuilder gsonBuilder = new GsonBuilder();
         MainConstructor mainConstructor = new MainConstructor(INSTANCE_CREATORS, true, REFLECTION_ACCESS_FILTERS);
+        if (sObjectToNumberStrategy != null) {
+            gsonBuilder.setObjectToNumberStrategy(sObjectToNumberStrategy);
+        }
         gsonBuilder.registerTypeAdapterFactory(TypeAdapters.newFactory(String.class, new StringTypeAdapter()))
                 .registerTypeAdapterFactory(TypeAdapters.newFactory(boolean.class, Boolean.class, new BooleanTypeAdapter()))
                 .registerTypeAdapterFactory(TypeAdapters.newFactory(int.class, Integer.class, new IntegerTypeAdapter()))

library/src/main/java/com/hjq/gson/factory/element/CollectionTypeAdapterFactory.java

@@ -7,6 +7,7 @@
 import com.google.gson.internal.ObjectConstructor;
 import com.google.gson.reflect.TypeToken;
 import com.hjq.gson.factory.constructor.MainConstructor;
+import com.hjq.gson.factory.other.ReflectiveTypeUtils;
 import java.lang.reflect.GenericArrayType;
 import java.lang.reflect.Type;
 import java.util.Collection;

library/src/main/java/com/hjq/gson/factory/element/ReflectiveTypeAdapter.java

@@ -9,6 +9,7 @@
 import com.google.gson.stream.JsonWriter;
 import com.hjq.gson.factory.GsonFactory;
 import com.hjq.gson.factory.ParseExceptionCallback;
+import com.hjq.gson.factory.other.ReflectiveFieldBound;
 import java.io.IOException;
 import java.util.Map;
 

library/src/main/java/com/hjq/gson/factory/element/ReflectiveTypeAdapterFactory.java

@@ -9,6 +9,8 @@
 import com.google.gson.internal.Excluder;
 import com.google.gson.reflect.TypeToken;
 import com.hjq.gson.factory.constructor.MainConstructor;
+import com.hjq.gson.factory.other.ReflectiveFieldBound;
+import com.hjq.gson.factory.other.ReflectiveTypeUtils;
 import java.lang.reflect.Field;
 import java.lang.reflect.GenericArrayType;
 import java.lang.reflect.Type;

library/src/main/java/com/hjq/gson/factory/other/AutoToNumberStrategy.java

@@ -0,0 +1,34 @@
+package com.hjq.gson.factory.other;
+
+import com.google.gson.ToNumberStrategy;
+import com.google.gson.stream.JsonReader;
+import java.io.IOException;
+import java.math.BigDecimal;
+
+/**
+ *    author : Android 轮子哥
+ *    github : https://github.com/getActivity/GsonFactory
+ *    time   : 2024/03/11
+ *    desc   : 自动转换数值类型的策略
+ */
+public class AutoToNumberStrategy implements ToNumberStrategy {
+
+    @Override
+    public Number readNumber(JsonReader in) throws IOException {
+        // Github issue 地址：https://github.com/getActivity/GsonFactory/issues/40
+        String numberString = in.nextString();
+        BigDecimal bigDecimal = new BigDecimal(numberString);
+        // 判断这个数值是浮点数还是整数
+        if (bigDecimal.scale() > 0) {
+            // 如果是浮点数，则用 double 类型装载
+            return bigDecimal.doubleValue();
+        }
+
+        // 如果是整数，则用 int 类型或者 long 类型装载
+        if (bigDecimal.compareTo(BigDecimal.valueOf(Integer.MAX_VALUE)) > 0) {
+            return bigDecimal.longValue();
+        } else {
+            return bigDecimal.intValue();
+        }
+    }
+}

library/src/main/java/com/hjq/gson/factory/element/ReflectiveFieldBound.java → library/src/main/java/com/hjq/gson/factory/other/ReflectiveFieldBound.java

@@ -1,8 +1,7 @@
-package com.hjq.gson.factory.element;
+package com.hjq.gson.factory.other;
 
 import com.google.gson.stream.JsonReader;
 import com.google.gson.stream.JsonWriter;
-
 import java.io.IOException;
 
 /**

library/src/main/java/com/hjq/gson/factory/element/ReflectiveTypeUtils.java → library/src/main/java/com/hjq/gson/factory/other/ReflectiveTypeUtils.java

@@ -1,4 +1,4 @@
-package com.hjq.gson.factory.element;
+package com.hjq.gson.factory.other;
 
 import com.google.gson.FieldNamingStrategy;
 import com.google.gson.Gson;
@@ -10,6 +10,10 @@
 import com.google.gson.stream.JsonReader;
 import com.google.gson.stream.JsonWriter;
 import com.hjq.gson.factory.constructor.MainConstructor;
+import com.hjq.gson.factory.element.CollectionTypeAdapter;
+import com.hjq.gson.factory.element.MapTypeAdapter;
+import com.hjq.gson.factory.element.ReflectiveTypeAdapter;
+import com.hjq.gson.factory.element.TypeAdapterRuntimeTypeWrapper;
 import java.io.IOException;
 import java.lang.reflect.Field;
 import java.math.BigDecimal;